Evaluation of endothelialization after percutaneous closure of paravalvular leaks.

BACKGROUND: There is limited data regarding the duration of endothelialization following paravalvular leak closure. We aimed to observe the endothelialization process in 2 patients who underwent surgery 6 and 16 months after failed percutaneous mitral paravalvular leak closure, respectively.
METHODS: Twodimensional transesophageal echocardiography (2D-TEE) and real-time 3-dimensional transesophageal echocardiography (RT-3D TEE) were utilized to demonstrate mitral paravalvular leaks. The status of endothelialization was explored in the surgery.
RESULTS: Two patients underwent percutaneous closure of mitral paravalvular leaks both with 2 occluder devices. The first patient was admitted with dyspnea 6 months later. RT-3D TEE demonstrated a defect around the proximal part of one of the occluder devices. The residual mitral regurgitation was considered moderate to severe by 2D TEE and RT-3D TEE. The patient was referred to surgery in which failed endothelialization of both devices was observed. In the second patient, 2 occluder devices were implanted. He underwent surgery at 16 months due to progressive increase in the severity of mitral regurgitation, which disclosed partially endothelialized closure device.
CONCLUSION: These cases suggest that endothelialization of closure devices may be significantly delayed or even absent for a long time following implantation.